Textile working units



Dec. 9, 1958 D, MEYER 2,863,175

TEXTILE WORKING UNITS Filed April 22, 1954 INVENTOR. DANIEL A. MEYER BY:5 ATT'Y.

2,863,?25 Patented Dec. 9, 12358 "rnrtrnn wonnnso UNITS Daniel. A.Meyer, Dayton, Uhio, assignorto TheDayton Rubber Company, a corporationof Ohio Application April 22, 1954, SerialNo. 424,810 7 Claims; ((ll.19--143) Theapresent invention relates to .textileworking. units,

and more particularly to cots or roll covers for spinning rolls. 7 Thisapplication is a continuation-in-part of copending application SerialNo. 336,129, filed February 10, 1953, and is restricted to the productclaims set forth therein, a requirement .for such restriction havingbeen made in the prosecution thereof.

A textileroller as used in present day drawing rovingtandspinningmachines, comprises a metal arbor having a sleeve-like rollcover known as a cot surroundingthe arbor. This cover is customarilymadeof leather, cork composition, or certain types of rubber compounds.

In the past, .most .textile cots were made of leather. These cotsprovedto benot too, satisfactory for use, on modern machines which work atrelatively highspeeds, due to poorresistance to lapping-up and'eyebrowing and due to their relatively short life. More recently, cotshave been made of .synthetiematerials which show considerably longerlife than leather and also possess better resistance to lapping-up andeyebrowingfi Despite the improved characteristics which have beenimparted to textile cots by the use of some of the known types ofsynthetic rubber, these cots, still donot function perfectly under allconditions and for ,all types of fibers. Some of the newer types ofcots, although considerably improved .over leather, still exhibit atendency toward eyebrowing. This condition results from the failure ofthe cot to carry the short fibers or clearer waste to the top clearer inorder to gather properly. Instead, theseshort fibers collect at theoutside edge of the top clearer and hang down over the roll. This.condition is called eyebrowing" and the mass of fibers which hangs downis called an eyebrow." As the size of the eyebrow increases, it willcontact the yarn and bunches of short fiber will be pulled into theyarn, thus impairing its quality.

In connection with the use of the various types of synthetic rubber-likecompositions for textile units and rollers of the type hereinconsidered, the incorporation of many substances with the rubber-likematerial has been proposed to improve their fiber working properties anduseful life. In Patent No. 2,373,876 to Cutler, the addition of graphitehas been proposed. The incorporation of rubber particles of a hardnessdiffering from the hardness of the main body of the roll has beenproposed in Patent No. 2,386,533 to Bacon; and Patent No. 2,393,953 toBacon discloses the use of fibrous materials such as cotton, rayon,glass, wool, bristles, hair, and the like. The inclusion of cork withinthe rubber-like composition of a roll cover is disclosed in Patents No.2,450,409 and No. 2,450,410 to Baymiller.

In pending applications owned by applicants assignee the combination ofother substances with the rubberlike composition has been proposed toeffect modification of the fiber drafting properties of textile units.

While the compositions proposed in these applications have representedsubstantial improvements over previously known textile cot compositionsand have been capable of operation for long periods oftime without theoccurrence of eyebrowing or lapping-up, any improvement Which willfurther increase the length of time which the textile unit-may operatewithout these deleterious tendencies is still to be desired;

To achieve this desired prolonged resistance to eyebrewing andlappingaup and thereby to increase the useful life of the textile.working unit, it is proposed to provide the same with a roll cover whichconsists of a rubber-like composition interspersed with which are aplurality. of small, smooth-surfaced, frangible particles. Theseparticles are to be of such a nature that they may be milled with therubber-like composition and remain.

embedded therein through the construction and vulcanization ofthe unit.At the same time, however, these pan ticles will be suflicientlyfrangible so that, upon subjection of the surface in which they areembedded to a grinding orabrading action, they will be broken, and, uponre moval of their fragments, will-leave in the working surface of theunit a plurality of cavities or voids in the shape of substantiallyspheroidal segments. Since the particles will be in substantiallyuniform distribution throughout the composition of at least the outerlayer of the roll cover, they will be exposed in varying degrees to theworkingsurface and the grinding action thereon. Many of those particleswhich are only slightly exposed to the surface,.however, will be brokenand, upon the removal of the fragments thereof will leave spheroidaldepressions the greatest circumference of which will lie beneath theactual working surface of the unit. The opening of such cavities uponthe working surface will be of smaller dimensions than those within thecavity.

It is therefore an object of the present invention. to i provide atextile working unit which will be capable of prolonged continuousoperation free from tendencies to eyebrow.

It is a further object of the present invention to provide a rubber-likeroll cover containing a plurality of small frangible particles, some ofwhich are exposed about the surface of the roll and may be broken. toleave a pattern of smooth-surfaced cavities thereon.

It is a still further object of the present invention to provide atextile drafting cot, the rubber-like surface composition of whichcontains a plurality of cavities in the shape of substantiallyspheroidal segments, the greatest circumference of which may lie on orbeneath the working surface.

Other features, advantages and objects of the present invention will beapparent from a reading of the following disclosure for theclarification and particularization of which reference may be had to theappended drawings.

In the drawings:

Figure 1 is a view in perspective of a typical fiber drafting cotconstituting a preferred embodiment of the present invention.

Figure 2 is a transverse section on the line 2-2 of Figure 1.

Figure 3 is a perspective, partially broken away, of a typical particlesuch as is proposed for inclusion within the rubber-like composition ofthe textile working unit of the present invention.

Figure 4 is a transverse section through a cot of this invention beforethe surface of the same has been prepared for operation.

In Figure 1 there is shown a roll or arbor it! which is usually composedof steel or a similar material. About this arbor and adhesivelyconnected thereto are shown the cots or roll covers 11 and Ho which,according to the present invention, are composed of a rubber-likecomposition and which, for purposes of illustration in the presentdescription, may be considered in their preferred form to be composed ofan oil-resistant copolymer of the butadiene-acrylic nitrile type alsoknown as Buna-N, Perbunan, GRA or by other well-known terms used in thetrade. About the surface 12 of this cot are shown the small cavities 13in the form of substantially spheroidal segments.

As best shown in Figure 2, these cavities extend to varying depthsbeneath the working surface of the cot. While the cavity at 14, forexample, is very shallow and presents only a slightly dished contour tothe working surface, that cavity at 15 extends considerably deeper intothe rubber composition, and, because of its depth and its substantiallyspheroidal shape, the diameter of its opening 16 upon the surface 12 issmaller than the diameter of its interior 15. The re-entrant portion ofrubberlike material formed by the reduction in diameter of thespheroidal cavity forms a resilient ring 17 about the opening of thecavity upon the periphery of the cot; and it is believed that this ringor re-entrant portion may be responsible for improved dissipation ofelectrostatic charge or the creation of improved'suction-like cups whichgreatly improve the eyebrowing and lapping-up resistance of the cot ofthe present invention.

As previously explained, the cavities such as .at 13, 14, and 15 areformed by the inclusion within the rubberlike composition of a pluralityof small, frangible, substantially spheroidal particles such as 19 ofFigure 3. In one preferred case, such particles have athin, ceramicshell 20 completely enclosing the hollow interior 21. If the material ofwhich they are made is of a sufiiciently frangible nature, however, theparticles may be solid spheres.

Upon the metal arbor 22 of Figure 4 is mounted a roll cover 23 after ithas been formed and vulcanized, but before its surface 24 has beenground to the necessary textile working regularity and smoothness. Ineven distribution throughout the rubber-like composition of the rollcover are shown the small particles 25 similar to the embedded particles18 in Figure 2. Those particles 26 immediately underlying the surface 24will be exposed to the surface and broken by the grinding of the roll,whereupon their broken particles may be removed to leave the previouslydescribed surface voids such as 13, 14 and 15.

While the quantity of the small particles per given weight will varyconsiderably as between those having a hollow interior and those whichare solid, it has appeared that the hollow particles, although lighterin Weight and more abundant relative to an equal weight of the solidparticles, break up more easily and thus compensate for their originallarger numbers, so that, in the final product, the number of surfacecavities will be approximately the same whether a given weight of hollowor solid particles is employed. Since it is the cavity formed by theseparticles which is of primary importance in the present invention, thesize of the particle employed does not depend upon Whether the particleis hollow or solid; and a broad range of particle sizes from 0.001 in.to 0.090 in. in diameter have been successfully employed.

One form of smooth, frangible particle satisfactory for incorporationwithin the rubber composition of a textile working unit according to thepresent invention is obtained by the fusion of argillaceous materialssuch as clays and shale, under such conditions that finely divided,hollow, spheroidal or substantially spherical particles are obtained.These particles are manufactured by feeding a ground and screened clayinto the top of a vertical furnace through which it falls and, While sodoing, passes through a gas-air flame whereupon it becomes heated to atemperature above 2700 F. causing it to become fused and expanded into ahollow ceramic particle and whereafter it cools during the remainder ofits fall. It is to be noted that these particles and the cavities formedby them have been enlarged in the drawings, for the sake of clarity.

These hollow, frangible particles 19 in the form of spheres or spheroidsare particularly desirable for purposes of the present invention inthat, because they are hollow, the particles may be easily broken intosmall fragments which, in turn, may be easily removed from the rubbercomposition leaving the desired cavities. On the other hand, theinherent structural strength of the particles resulting from theirspherical shape will resist ordinary internal forces within the cotduring its manufacture and operation so that they will remain integraland have no deteriorating effect upon the rubber composition until theyare exposed to the working surface at which time they may be broken andthe would-bedeleterious fragments effectively removed.

The rubber composition to be used in the roll covers may be similar toany of the known synthetic rubber-like compounds previously employed forsuch applications and may be prepared according to well-known proceduresfrom the various well-known compounding ingredients, the pro-perselection of which may be readily made by those skilled in the art. Apreferred example of such a composition is as follows:

' Parts by weight The preferred amount of particles to be incorporatedwith such a rubber-like polymer will vary in direct proportion to thedegree of fiber spinning and/or twisting to be accomplished by thetextile machine unit .and will also vary according to the chemical andstructural nature of the particles. While satisfactory cots haveincluded from 30 to 150 parts by weight of the particles to parts byweight of the rubber-like polymer, there is no indication that theutility of this invention is limited to such a range of proportions,especially where varying particle sizes are employed.

Small spheres or beads of glass, which is a siliceous material usuallyformed from silica and an alkali such as sodium hydroxide or potassiumhydroxide, have also been found satisfactory for inclusion in cotsaccording to the present invention. Where these beads are in solidspherical form, the significance of their frangibility is enhanced sincethe problems involved in breaking and removing the broken fragments of asolid body are greater than in the case of a hollow one. These problemsnotwithstanding, the glass beads may be satisfac torily broken bygrinding and their fragments removed by blowing or bufiing to providethe desired spheroidal voids and cavities as described above. To aid inthis process, the glass from which the beads are formed may becompounded so as to be more frangible as for example, by the addition oflead oxide according to common practices in the manufacture of crystalor flint glass.

One preferred compound incorporating the glass heads is as follows:

Parts by weight Butadiene-acrylic nitrile copolymer 100 Plasticizer(tricresyl phosphate) 12.5 Stearic acid .625 Sulfur 6.5 Antioxidant (dibeta naphthyl para phenylenediamine) Accelerator (benzothiazyldisulfide) 1.25

Coumarone indene resin 7.5 Soft clay filler 30 Solid glass beads (0.006in. to 0.017 in. diameter) 60 The spherical materials are preferablythoroughly mixed in the rubber-like matrix composition during theregular mixing involved in the compounding thereof, such mixing takingplace on a mill or in a Banbury as is the common custom in compoundingrubber-like material. The matrix material thus compounded and carryingthe spheroidal particles is then preferably extruded in tubular formupon a building mandrel or directly upon the arbor of the roll of whichthe cot is to form the covering. The material thus formed and mounted isthen subjected to vulcanizing conditions according to the common andwell-known practice, usually by rag wrapping and placing the assembly inan open steam vulcanizer. During this vulcanization the rubber-likematrix composition will assume its elastomeric properties and thespherical particles will become permanently set therein. The plasticflow of the matrix composition attending this vulcanization is such thatthe particles near the surface of the roll cover will be covered with athin fiim of the rubber-like material. Accordingly, to uncover thesurface particles and to remove the impression of the rag wrapper, theroll covers are removed from the vulcanizer and subjected to a grindingand buffing action until they are brought to proper working dimensions.It is during this grinding operation that the surface particles becomebroken into small fragments which may be easily removed to leave thedesired voids and cavities as above described.

The working surface of the cot, once abraded and blown so as to removethe broken fragments of the ceramic-like particles, will benon-regenerating; that is, the cot or similar textile working unit willnot wear away to the extent that the cavities formed by the brokenparticles will be worn away and new unbroken particles appear on thesurface. When the cot begins to lose its desirable properties withregard to resistance to eyebrowing and lapping-up it may be subjected toa new grinding or abrading action as is the established custom in thetextile art. In order that the broken fragments of the frangibleparticle will not remain on the cot to the damage of the goods beingworked and the bearings and other parts of the textile working machine,each grinding operation will be followed by blowing or similar means toremove the broken particle fragments from the rubber-like composition.

The superiority of a textile cot made according to the present inventionwith regard to its non-eyebrowing characteristics and its increasedoperational life between working surface renewal has been clearlydemonstrated in the hereinafter described tests wherein the cot of thisinvention was compared with previously known cots. In the table below,cot A represents a cot of a typical butadiene-acrylic nitrilecomposition without the addition of any particles. Cot B was of asimilar compound containing granulated cork particles evenly distributedtherethrough. Cot C included the small, frangible particles according tothe present invention. All of these cots were run on a typical drawingframe at high speeds approximating those normally used for the rovingoperation in which eyebrowing has been found most difiicult to control.The hours which each cot, operating under the same test conditions, ranbefore eyebrowing began to appear were as follows:

Hours to eyebrow Cot A /2 to Cot B 60 to 95 Cot C over 400 It is obviousfrom these results that the cot according to the present inventionconstitutes an important step forward in the art insofar as cot Ccontaining the small, hollow, frangible particles performed from four tofive times as long as the previously known types without eyebrowing. Inpractice this means that replacement, resurfacing of the cots and thelabor cost, and loss of time involved therein will be substantiallyreduced.

Although, in the foregoing description, particular reference has beenmade to preferred singular embodiments of the present invention, it isto be understood that the terms and examples employed therein are forpurposes of description only and are in no way intended to limit thescope of the principles of this invention as defined in the followingclaims.

l' claim:

i. A roll of synthetic oil-resistant rubber-like composi tion containinga plurality of small, smooth-surfaced, hollow, frangible particlesinterspersed therein.

2. A roll of synthetic oil-resistant rubber-like composition, the outerportion of which comprises a plurality of small, substantiallyspherical, hollow, frangible particles of a fused siliceous material andthe working surface of which comprises a plurality of cavities in theshape of substantially spherical segments formed by the breakage andremoval of the frangible particles therefrom.

3. A textile fiber drafting cot comprising a synthetic rubber-likebutadiene-acrylic nitrile copolymer composition interspersed with whichare a plurality of small, smooth-surfaced, substantially spherical,hollow, frangible particles of a fused and expandedargillaceous'material wherein the surface portion of said cot comprisesa plurality of voids in the form of spheroidal segments formed by thebreakage and removal of the frangible particles therefrom.

4. A textile cot according to claim 3 wherein the openings of asubstantial proportion of said voids upon said working surface aresubstantially circular and are of a smaller diameter than the interiorof said voids.

5. A textile cot according to claim 3 wherein the siliceous material isclay.

6. A textile fiber working unit of a rubber-like compositioninterspersed with which are a plurality of small, frangible,substantially spheroidal particles wherein the working surface of saidunit comprises a plurality of depressions in the form of substantiallyspheroidal segments left upon the removal of said particles therefromand a substantial proportion of said depressions have an internaldiameter which is greater than the diameter of their opening upon saidsurface.

7. The article of claim 6 in which said unit cot.

is a drafting References Cited in the file of this patent UNITED STATESPATENTS 257,308 Flagg May 2, 1882 1,041,074 Harris Oct. 15, 19121,563,943 Adams et al. Dec. 1, 1925 2,062,317 Joseph Dec. 1, 19362,386,583 Bacon Oct. 9, 1945 2,393,953 Bacon Feb. 5, 1946 2,569,546Treue Oct. 2, 1951 FOREIGN PATENTS 764,663 France May 25, 1934

